Structural and electron transport investigations of functionalized carboxylic acids on Cu(110)-surfaces: experimental and ab initio studies

• Applicant: Dr.-Ing. Silvia Karthäuser
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2006 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 25125753

Our aim is to investigate the structure and the electronic transport through the carboxylate-Cu(110) interface, experimentally and theoretically, and to use these data to build up a molecular device, which is based on the exploitation of the different electron transport paths through these molecules. Basic geometries and electron transport properties will be investigated using the carboxylic acids with systematically varying substituents adsorbed in different configurations on the Cu(110)-substrate to deduce the influence of the HOMO/LUMO gap on the intermolecular and molecule-substrate coupling. Experimentally we aim to combine differential conductance measurements and inelastic tunneling spectroscopy with high resolution UHV-STM to get the energy levels and the electron-phonon coupling of the carboxylic acids in a thoroughly defined environment. Theoretically we aim at combining ab initio methods to describe structural and transport properties to deduce the theoretical parameters to predict structures of carboxylic acids, which are stable in two conductive states so that they have the potential to be used as electronic devices. Furthermore we intend to chemically modify the carboxylic monolayers or embed single molecules in situ and to develop a further tool to create new structures for electronic devices. Finally we will use the electron transport through the intermolecular ¿-¿ interaction of carboxylic acids to modulate the electron transport vertical through the molecule and to build up a molecular device.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1243: Quantum Transport at the Molecular Scale
• Participating Persons: Dr. Nicolae Atodiresei; Professor Dr. Stefan Blügel